How is Montgeron run?
Sylvie Carillon has been mayor of Montgeron since March 29, 2026, elected by the 35 members of the municipal council. At the March 2026 municipal elections, Montgeron pour la vie ! won 27 of the 35 seats in the second round on March 22, 2026, with 48.9% of the votes. Montgeron is part of the Communauté d'agglomération Val d'Yerres Val de Seine.
March 2032
Councils are elected for six years; the council elects the mayor.
Register to vote ↗Throughout this page, the median in Essonne and the France median are the median of compared communes (those with an overall grade), each figure its own median.
The council the voters chose
Seats as the March 2026 results gave them, one dot a seat.
- Montgeron pour la vie !276 community seats
- Montgeron en commun 202662 community seats
- Engagés pour Montgeron20 community seats
As elected in the second round, March 22, 2026.
The list that comes first gets half the seats; the rest are shared in proportion among the lists with 5% or more, the winner included. So the winning list always has a majority. The same vote gave Montgeron 8 seats on the council of the Communauté d'agglomération Val d'Yerres Val de Seine (community seats).
Source: Interior ministry, 2026 municipal election results (March 15 and 22), subject to corrections and appeals.
4 authorities share the work
The commune is the tier closest to residents; the intercommunality, the département and the région do the rest.
Births, marriages and deaths, the electoral roll, nursery and primary schools, local roads, planning permission, the municipal police, and what else the council takes on.
Mayor: Sylvie Carillon · 35 councilors
The services its communes share: usually waste collection, economic development and planning documents; often water and local buses.
Social aid (RSA, care for older and disabled people, child protection), collèges, the département’s roads, and funding for fire and rescue.
Lycées, regional trains (TER) and coaches, economic development and job training.
Who to ask
The usual split of powers (service-public.fr); an intercommunality’s exact remit varies, so check its website for waste, water and buses.
Membership: COG 2026 (INSEE); intercommunality type: BANATIC, January 2025. What each tier does: service-public.fr.
From the mayor to the intercommunality
The officials as the Interior ministry’s register lists them, and the council by list.
- 1Mayorsince March 29, 2026Sylvie Carillon
- 2Deputy mayors9 adjoints, elected by the councilPierre-Valéry GaudeauValérie DollfusClément VeyratSandrine GueryChristian CorbinGraziella Riou-HarchaouiMaurice KnafoMartine Poulet+1 more
- 3Montgeron municipal council35 seats by listMontgeron pour la vie ! 27 · Montgeron en commun 2026 6 · Engagés pour Montgeron 2
- 4Communauté d'agglomération Val d'Yerres Val de SeineMontgeron holds 8 seatsCommunity councilors are drawn from the council lists in the same vote.
Source: Interior ministry, national register of elected officials (RNE), August 11, 2026.
The 35 members of the Montgeron municipal council
The mayor and 9 deputy mayors first, then the councilors.
| Name | Office | Since |
|---|---|---|
| Sylvie Carillon | Maire | March 29, 2026 |
| Pierre-Valéry Gaudeau | 1er adjoint au Maire | March 29, 2026 |
| Valérie Dollfus | 2ème adjoint au Maire | March 29, 2026 |
| Clément Veyrat | 3ème adjoint au Maire | March 29, 2026 |
| Sandrine Guery | 4ème adjoint au Maire | March 29, 2026 |
| Christian Corbin | 5ème adjoint au Maire | March 29, 2026 |
| Graziella Riou-Harchaoui | 6ème adjoint au Maire | March 29, 2026 |
| Maurice Knafo | 7ème adjoint au Maire | March 29, 2026 |
| Martine Poulet | 8ème adjoint au Maire | March 29, 2026 |
| Fabrice Allard | 9ème adjoint au Maire | March 29, 2026 |
Show the full council (35)
| Name | Office | Since |
|---|---|---|
| Sylvie Carillon | Maire | March 29, 2026 |
| Pierre-Valéry Gaudeau | 1er adjoint au Maire | March 29, 2026 |
| Valérie Dollfus | 2ème adjoint au Maire | March 29, 2026 |
| Clément Veyrat | 3ème adjoint au Maire | March 29, 2026 |
| Sandrine Guery | 4ème adjoint au Maire | March 29, 2026 |
| Christian Corbin | 5ème adjoint au Maire | March 29, 2026 |
| Graziella Riou-Harchaoui | 6ème adjoint au Maire | March 29, 2026 |
| Maurice Knafo | 7ème adjoint au Maire | March 29, 2026 |
| Martine Poulet | 8ème adjoint au Maire | March 29, 2026 |
| Fabrice Allard | 9ème adjoint au Maire | March 29, 2026 |
| Samia Benzarti | Conseiller municipal | March 22, 2026 |
| Élise Billebault | Conseiller municipal | March 22, 2026 |
| Martine Boulay | Conseiller municipal | March 22, 2026 |
| Yann Chevert | Conseiller municipal | March 22, 2026 |
| Céline Ciéplinski | Conseiller municipal | March 22, 2026 |
| François Durovray | Conseiller municipal | March 22, 2026 |
| Christian Ferrier | Conseiller municipal | March 22, 2026 |
| Lenaïc Ferrier | Conseiller municipal | March 22, 2026 |
| Isabelle Gartenlaub | Conseiller municipal | March 22, 2026 |
| Géraud Goury | Conseiller municipal | March 22, 2026 |
| Sami Hidri | Conseiller municipal | March 22, 2026 |
| Agathe Laporte | Conseiller municipal | March 22, 2026 |
| Yannick Le Meur | Conseiller municipal | March 22, 2026 |
| Franck Leroy | Conseiller municipal | March 22, 2026 |
| Eric Magadoux | Conseiller municipal | March 22, 2026 |
| Isabelle Marques | Conseiller municipal | March 22, 2026 |
| Stefan Milosevic | Conseiller municipal | March 22, 2026 |
| Agnès Morin | Conseiller municipal | March 22, 2026 |
| Françoise Nicolas | Conseiller municipal | March 22, 2026 |
| Alida Poivre | Conseiller municipal | March 22, 2026 |
| Guillaume Prim | Conseiller municipal | March 22, 2026 |
| Pierrette Provost | Conseiller municipal | March 22, 2026 |
| Oumar Soumare | Conseiller municipal | March 22, 2026 |
| Caroline Touchon | Conseiller municipal | March 22, 2026 |
| Jean-François Vincent | Conseiller municipal | March 22, 2026 |
Names and offices as the Interior ministry’s national register of elected officials (RNE) published them on August 11, 2026, written as it writes them. Public role only. Later resignations and replacements aren’t shown.
The council: same source as Who represents Montgeron, above.
How Montgeron voted in March 2026
4 lists stood in the first round; none won half the votes, so a second round followed.
8,978 votes cast for a list
9,120 of 15,891 registered voters in Montgeron voted.
83 blank and 59 spoilt ballots, not counted in the shares.
8,996 votes cast for a list · no seats given out: a second round followed
9,146 of 15,886 registered voters in Montgeron voted.
102 blank and 48 spoilt ballots, not counted in the shares.
Turnout, first round · March 15, 2026
Shares are of the votes cast for a list, leaving out blank and spoilt ballots. Lists in vote order; the colors only tell the lists apart.
2026 elections: same source as Who’s in charge, above.
Montgeron spends €1,826 per resident a year
The commune’s consolidated accounts: main and annexed budgets, transfers between them removed.
Per resident, 2025 · against compared communes
Spending and debt per resident, 2018 to 2025
Montgeron owed €17.5M at the end of 2025, €724 per resident, lower than in 52% of compared French communes, equal to 58% of a year’s running costs.
Show year by year
| Year | Spending | Investment | Debt | Debt in all |
|---|---|---|---|---|
| 2025 | €1,826 | €584 | €724 | €17.5M |
| 2024 | €1,662 | €468 | €834 | €20.1M |
| 2023 | €1,618 | €404 | €847 | €20.5M |
| 2022 | €1,544 | €409 | €936 | €22.5M |
| 2021 | €1,411 | €350 | €909 | €21.9M |
| 2020 | €1,436 | €410 | €1,012 | €24.4M |
| 2019 | €1,511 | €479 | €1,025 | €24.9M |
| 2018 | €1,533 | €420 | €1,005 | €24.1M |
Source: OFGL, consolidated commune accounts 2018–2025 (DGFiP); 2025 provisional.
The 15th lowest debt per resident of 41 communes its size
The 40 compared communes nearest in population, debt per resident at the end of 2025.
Lowest: Rodez, €33. Highest: Vichy, €4,044.
Have a say in Montgeron
French citizens register online or at the town hall; citizens of other EU countries can vote in municipal elections too.
service-public.fr ↗See where you’re registered and which polling station is yours.
service-public.fr ↗Council meetings are public; the agenda and minutes are posted at the town hall and usually on its website.
service-public.fr ↗Opening hours, address and phone number of the mairie of Montgeron in the public services directory.
lannuaire.service-public.fr ↗Who can stand, how lists are formed and the deadlines, from the Interior ministry.
interieur.gouv.fr ↗What this data can and can’t tell you
- Mayors and councilors. From the Interior ministry’s national register of elected officials (RNE) as published on August 11, 2026: name, office and start dates, nothing else. The register counts a mayor as a councilor too; the page counts each person once. It isn’t a live roll: resignations and replacements after that date aren’t shown, and no party is inferred for any official.
- How the council is elected. Since March 2026 every commune elects its council from lists (a 2025 law extended list voting to communes under 1,000). A list with more than half the votes in the first round wins; otherwise lists with 10% or more can go on to a second round, where the list ahead wins. It gets half the seats, and the rest are shared in proportion among lists with 5% or more. The council then elects the mayor and the deputy mayors.
- The label beside a list. The political nuance the prefecture gave the list for the ministry’s results (Divers droite, Union de la gauche…), shown as published. It isn’t the list’s own description; many lists, most in small communes, have none.
- The commune’s money. OFGL’s consolidated accounts from the DGFiP, 2018 to 2025; 2025 is provisional. Spending and investment leave out loan repayments; running costs are part of spending. Debt is what was owed at the end of the year.
- Per resident. Divided by the DGFiP’s population for that year (population totale, which counts some people, such as boarding students, in two communes), so it can differ from the census figure elsewhere on the site.
- The medians. Beside the town’s figure, the median of compared communes in its département and in France (those with an overall grade). A commune’s spending follows its size and its role: one that runs a pool or a theater for the villages around it spends more per resident.
Questions about Montgeron’s town hall
Who is the mayor of Montgeron?
Sylvie Carillon, mayor since March 29, 2026, according to the Interior ministry’s register of elected officials (August 11, 2026).
How many councilors does Montgeron have?
The Montgeron municipal council has 35 members, the mayor and 9 deputy mayors included.
Who won the 2026 municipal elections in Montgeron?
Montgeron pour la vie !, in the second round on March 22, 2026, with 48.9% of the votes; it holds 27 of the 35 seats.
What was the turnout in Montgeron?
57.6% of registered voters voted in the first round on March 15, 2026; the median of compared French communes was 57.4%.
When are the next municipal elections in Montgeron?
Councils are elected for six years, so the next general municipal elections are due in March 2032. A council can be re-elected sooner if it loses too many members.
How much debt does Montgeron have?
€17.5M at the end of 2025, €724 per resident; the median of compared French communes was €748.
Which intercommunality is Montgeron part of?
Montgeron is part of the Communauté d'agglomération Val d'Yerres Val de Seine, which runs the services its communes share.
Sources: Interior ministry RNE, August 11, 2026 · Interior ministry, municipal results 2026 · OFGL consolidated commune accounts 2018–2025 · INSEE COG 2026 and BANATIC (January 2025) for the intercommunality. Under the Licence Ouverte / Open Licence 2.0 (Etalab).
Contains public sector information under the Licence Ouverte / Open Licence 2.0 (Etalab): INSEE, DGFiP, the Interior Ministry’s statistics service (SSMSI), the Ministry of Education (DEPP), the Health Ministry’s statistics service (DREES) and the Housing Ministry (Carte des loyers). Commune boundaries: IGN Admin Express.